Light emitting device

ABSTRACT

A light emitting device includes a package body, a light emitting diode, a transparent resin material, and a wire. The package body includes a bottom part and a side part. The bottom part includes a first electrode and a second electrode electrically connecting the upper surface and the bottom surface of the bottom part, respectively. The side part includes an upper surface including a trench and a bottom surface being in contact with the upper surface of the bottom part, wherein the upper surface of the bottom part is lower than the upper surface of the side part such that the package body includes a cavity surrounded by the side part, and the bottom surface of the bottom part includes a second opened portion that divides the first electrode and the second electrode, and wherein a portion of the transparent resin material is disposed inside of the trench.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuous application of Ser. No. 12/436,522filed on May 6, 2009, and claims priority under 35 U.S.C. 119 to KoreanPatent Application No. 10-2008-0042236, filed on May 7, 2008, which arehereby incorporated by reference in their entirety.

BACKGROUND

Embodiments relate to a semiconductor light emitting device.

Light Emitting Diodes (LEDs) use GaAs, GaN, InGaN and InGaAlP-basedcompound semiconductor materials to constitute a light emitting source,thereby realizing various colors.

Characteristics of the LEDs are determined depending on materials,colors, brightness and brightness intensity of the compoundsemiconductor materials. In addition, the LEDs are fabricated in theform of package and are applied to various fields of a lighteningindicator, a character displayer and an image displayer.

SUMMARY

Embodiments provide a light emitting device comprising a package bodycomprising a trench around a light emitting diode.

Embodiments provide a light emitting device in which a cavity and atrench are defined on/around a package body to prevent a resin fromoverflowing.

An embodiment provides a light emitting device comprising: a packagebody including a bottom part having a first electrode and a secondelectrode, a side part having a trench, and a cavity, a light emittingdiode disposed on the first electrode, a transparent resin materialdisposed inside of the cavity, and a wire connecting the light emittingdiode to at least one of the first electrode and the second electrode,wherein the bottom part having an upper surface and a bottom surface,wherein the bottom part includes a first electrode and a secondelectrode electrically connecting the upper surface and the bottomsurface of the bottom part, respectively, wherein a side part has anupper surface including the trench and a bottom surface being in contactwith the upper surface of the bottom part, wherein the upper surface ofthe bottom part is lower than the upper surface of the side part suchthat the package body includes a cavity surrounded by the side part,wherein the upper surface of the bottom part includes a first openedportion that divides the first electrode and the second electrode, andthe bottom surface of the bottom part includes a second opened portionthat divides the first electrode and the second electrode, and wherein aportion of the transparent resin material is disposed inside of thetrench.

The details of one or more embodiments are set forth in the accompanyingdrawings and the description below. Other features will be apparent fromthe description and drawings, and from the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side-sectional view of a light emitting device according toa first embodiment.

FIG. 2 is a plan view illustrating a trench of a package body of FIG. 1.

FIG. 3 is a side-sectional view of FIG. 2.

FIG. 4 is a plan view of a light emitting device according to a secondembodiment.

FIG. 5 is a plan view of a light emitting device according to a thirdembodiment.

FIG. 6 is a perspective view of a light emitting device according to afourth embodiment.

FIG. 7 is a side-sectional view of a light emitting device according toa fifth embodiment.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Hereinafter, a light emitting device according to embodiments will bedescribed with reference to the accompanying drawings.

FIG. 1 is a side-sectional view of a light emitting device according toa first embodiment, FIG. 2 is a plan view illustrating a trench of apackage body of FIG. 1, and FIG. 3 is a side-sectional view of FIG. 2.

Referring to FIGS. 1 to 3, a light emitting device 100 comprises apackage body 110 having a cavity 101 and a trench 130, electrodes 112and 114, a light emitting diode 120, a resin material 140, and a lens150. The light emitting device 100 may be defined as a light emittingdiode package. This term may be variously defined within the technicalscope of embodiments.

For example, the package body 110 may be formed of a material having ahigh insulating property or a high thermal conductivity such as silicon,silicon carbide (SiC), and aluminum nitride (AlN). Hereinafter, forconvenience of description, the package body 110 will refer to as asilicon-based wafer level package (WLP).

The package body 110 may comprise a frame having a polyhedral shape. Thepackage body 110 may have the same length as each other or lengthsdifferent from each other in horizontal and vertical length, but it isnot limited thereto.

The cavity 101 is defined in an inner upper portion of the package body110. A predetermined etching process, e.g., a wet etching process and/ora dry etching process may be performed on the package body 110 to formthe cavity 101 having a vessel (or a bathtub) shape or a depressedstructure.

A lateral surface 117 of the cavity 101 may be perpendicular to a bottomsurface of the cavity 101 or inclined outwardly with respect to avertical shaft.

The cavity 101 of the package body 110 may have a single layer or amulti-layer structure. In case of the cavity 101 having the multi-layerstructure, at least one cavity may be further defined in a portion ofthe bottom surface of the cavity 101.

Referring to FIGS. 2 and 3, the trench 130 is defined around a topsurface of the package body 110. The trench 130 is disposed along anouter circumference of the cavity 101 by a predetermined depth. Thetrench 130 may have a shape different from an outer shape of the cavity101, e.g., a circular or an oval shape.

Referring to FIG. 3, the trench 130 may have a depth less than about 30um from a top surface 103 of the package body 110. The depth of thetrench 130 may be defined by considering prevention of resin overflowand electrode formation.

The dry etching process and/or the wet etching process may be performedto form the trench 130. In detail, in the dry etching process, a masklayer may be formed on a surface of the package body 11, and then, themask layer may be patterned to form a mask pattern having a desiredshape using exposing, developing, and etching processes ofphotolithography processes. An open region having a trench shape isformed using the mask pattern, and then, the dry etching process isperformed. Reactive ion etching (RIE), magnetically enhanced reactiveion etching (MERIE), inductively coupled plasma (ICP) processes usingplasma may be selectively performed in the dry etching process. The dryetching process may be performed on the package body 110 to form thetrench 130 having the predetermined depth (e.g., less than about 30 um).

In the wet etching process, when the mask pattern having the circular oroval shape is formed on the surface of the package body 110, the trench130 having the predetermined depth may be formed using a wet etchingsolution.

The wet etching process may be performed after the dry etching process.At this time, the wet etching process is an isotropic wet etchingprocess. At least one of an acetic acid, a hydrofluoric acid, and anitric acid may be used as the wet etching solution, or a solution inwhich the etching solutions are mixed at a predetermined ratio may beused as the wet etching solution.

The trench 130 may be formed in the package body 110 before or after thecavity 101 is formed. The trench 130 may have a close-loop shape inwhich a cut portion does not exist or an open-loop shape in which thecut portion exists.

The plurality of electrodes 112 and 114 are disposed on the surface ofthe package body 110. The electrodes 112 and 114 are divided by anopened portion 115 through which the top surface of the package body 110is partitioned into both sides. Each of the electrodes 112 and 114 mayextend from the bottom surface of the cavity 101 up to the top surface,a lateral surface, and a bottom surface of the package body 110. Bothends of the electrodes 112 and 114 may be disposed on the bottom surfaceof the package body 110 and used as external electrodes P1 and P2. Theelectrodes 112 and 114 may be disposed on the trench 130 and in a regionexcept the opened portion 115.

E-beam, sputtering, and electro plating deposition processes may beperformed to form the electrodes 112 and 114.

The plurality of electrodes 112 and 114 may have different electrodepatterns according to a structure of the cavity 101 and a mountingposition of the light emitting diode 120, respectively, but it is notlimited thereto. Any one of the plurality of electrodes 112 and 114 mayhave a via structure.

At least one light emitting diode 120 is disposed on the cavity 101 ofthe package body 110. An LED chip may be used as the light emittingdiode 120.

The light emitting diode 120 may selectively comprise a red LED chip, ablue LED chip, a green LED chip, an ultraviolet (UV) LED chip, and ayellow LED chip, but it is not limited thereto. An electrostaticprotection device may be mounted on the package body 110, or an ionimplantation or diffusion process may be performed on the package body110 to realize the electrostatic protection device. The electrostaticprotection device may be realized as a zener diode for protecting thelight emitting diode 120.

The light emitting diode 120 may be connected to the plurality ofelectrodes 112 and 114 using wires 120. Wire bonding, die bonding, andflip bonding processes may be selectively performed according to thechip types of the light emitting diode 120 to connect the light emittingdiode 120 to the electrodes 112 and 114. The connection structure of thelight emitting diode 120 may be variously modified according to a typeof LED chip, the number of LED chip, and patterns of the electrodes 112and 114, but it is not limited thereto.

The resin material 140 is filled into the cavity 101. The resin material140 may comprise a transparent insulating material, e.g., a resinmaterial such as an epoxy resin or silicon or a polymer material, but itis not limited thereto. A liquid resin material is dispensed to form theresin material 140.

At least one phosphor of phosphors (not shown) such as red, green, andblue phosphors may be added to the resin material 140, and this may bechanged within the technical scope of embodiments.

The resin material 140 seals portions of the light emitting diode 120and the electrodes 112 and 114 to protect them. The lens 150 is disposedon the resin material 140. A transparent resin material may be dispensedto form the lens 150 before or after the resin material 140 is hardened.The lens 150 may be changed in shape according to a shape of the trench130 and an amount of the dispensed resin material.

The trench 140 may prevent the resin material dispensed for forming thelens 150 from overflowing. Thus, an outer shape of the lens 150 may beuniform.

The outer shape and size of the lens 150 may be changed according to theshape and size of the trench 140. For example, when the trench has thecircular shape, the outer shape of the lens 150 may have a circularshape. Also, when the trench has the oval shape, the outer shape thelens 150 may have an oval shape. An orientation angle may be adjustedaccording to the shape of the lens 150 using the trench 130.

A process for manufacturing the light emitting device according to thefirst embodiment will now be roughly described.

The cavity 101 is formed in the inner upper portion of the package body110, and the trench 130 is formed around the outside of the cavity 101.The plurality of electrodes 112 and 114 are formed on the package body110 and the surface of the cavity 101. The light emitting diode 120 ismounted on the electrodes 112 and 114. The resin material is formed inthe cavity 101, and the lens 150 is formed inside the trench 130 on theresin material 140.

FIG. 4 is a plan view of a light emitting device according to a secondembodiment. In the following description of the second embodiment,duplicate descriptions for elements which are the same as those of thefirst embodiment will be omitted.

Referring to FIG. 4, in a light emitting device 100A, a trench 130 isdisposed around a cavity 101 of a package body 110.

The trench 130 may have a circular shape and be divided into a pluralityof trenches 130A and 130B that does not communicate with each other.Both ends of the plurality of trenches 130A and 130B are spaced apredetermined gap 113 from an opened portion 115. Thus, the openedportion 115 may divide the plurality of trenches 130A and 130B and aplurality of electrodes 112 and 114 into both sides thereof.

When the trenches 130A and 130B are not formed in the opened portion115, it may prevent the plurality of electrodes 112 and 114 from beingelectrically shorted within the opened portion 115.

Two or more trenches 130 may be formed, and each of the trenches mayhave the circular shape. The number of trenches may be changed withinthe technical scope of embodiments.

FIG. 5 is a plan view of a light emitting device according to a thirdembodiment. In the following description of the third embodiment,duplicate descriptions for elements which are the same as those of thefirst embodiment will be omitted.

Referring to FIG. 5, a light emitting device 100B comprises a packagebody 110A having a rectangular shape and a cavity 101A having arectangular shape. The package body 110A has a horizontal length X and avertical length Y which are different from each other. The cavity 101Ahaving the rectangular shape may be disposed inside the package body110A. The cavity 101A may have a shape different from that of thepackage body 110A, e.g., a square or circular shape, but it is notlimited thereto.

A trench 130 is disposed around the outside of the cavity 101A. Thetrench 130 may have an oval shape. A lens 150 having an oval shape maybe manufactured by the trench 130. Light may be oriented in a specificdirection or in a specific region due to the lens 150.

The light emitting device 100B may have a large orientation angle in anX-axis direction and a small orientation angle in a Y-axis direction dueto the cavity 101A having the rectangular shape and the lens 150 havingthe oval shape.

FIG. 6 is a perspective view of a light emitting device according to afourth embodiment. In the following description of the fourthembodiment, duplicate descriptions for elements which are the same asthose of the first embodiment will be omitted.

Referring to FIG. 6, a light emitting device 100C comprises a packagebody 110 in which a cavity 101B having a circular shape is provided. Anouter shape of the cavity 101B has the circular shape.

A resin material is filled in the cavity 101B, and a lens 150 isdisposed on the resin material. An outer surface of the lens 150 isdisposed along the trench 130.

The trench 130 is spaced the same distance from a circumference of thecavity 101B. Also, the outer surface of the lens 150 may be spaced thesame distance from the circumference of the cavity 101B. Thus, lightemitted from the lens 150 may be irradiated with a smooth distribution.

Dry and wet etching processes may be selectively performed to form thecavity 101B having the circular shape. When the wet etching process isperformed after the dry etching process is performed, an isotropic wetetching process is performed. Thus, the cavity 101B may have a lateralsurface 117 curved with a predetermined curvature.

The trench 130 of the package body 110 may be formed after the cavity101B is formed first, and the process procedure may be changed.

FIG. 7 is a side-sectional view of a light emitting device according toa fifth embodiment. In the following description of the fifthembodiment, duplicate descriptions for elements which are the same asthose of the first embodiment will be omitted.

Referring to FIG. 7, a light emitting device 100D has a flat top surfacewithout forming a cavity on a package body 110.

A trench 130 having a circular or oval shape is disposed around an outertop surface of the package body 110. A plurality of electrodes 112 and114 may be disposed around the outer top surface of the package body110. A light emitting diode 120 is attached in the inside or a centralregion of the trench 130. The light emitting diode 120 is electricallyconnected to the plurality of electrodes 112 and 114.

According to the fifth embodiment, the number of processes for formingthe cavity in the silicon-based package body 110 may be reduced.

Technical characteristics of the first to fifth embodiments are notlimited to a characteristic of each of the embodiments, and anyembodiment may be selectively applied to another embodiment within thetechnical scope of the embodiments.

In the description of embodiments, it will be understood that when alayer (or film), region, pattern or structure is referred to as being‘on’ another layer (or film), region, pad or pattern, the terminology of‘on’ and ‘under’ comprises both the meanings of ‘directly’ and‘indirectly’. Further, the reference about ‘on’ and ‘under’ each layerwill be made on the basis of drawings.

Any reference in this specification to “one embodiment,” “anembodiment,” “example embodiment,” etc., means that a particularfeature, structure, or characteristic described in connection with theembodiment is comprised in at least one embodiment of the invention. Theshapes of such phrases in various places in the specification are notnecessarily all referring to the same embodiment. Further, when aparticular feature, structure, or characteristic is described inconnection with any embodiment, it is submitted that it is within thepurview of one skilled in the art to effect such feature, structure, orcharacteristic in connection with other ones of the embodiments.

Although embodiments have been described with reference to a number ofillustrative embodiments thereof, it should be understood that numerousother modifications and embodiments can be devised by those skilled inthe art that will fall within the spirit and scope of the principles ofthis disclosure. More particularly, various variations and modificationsare possible in the component parts and/or arrangements of the subjectcombination arrangement within the scope of the disclosure, the drawingsand the appended claims. In addition to variations and modifications inthe component parts and/or arrangements, alternative uses will also beapparent to those skilled in the art.

What is claimed is:
 1. A light emitting device comprising: a packagebody including: a bottom part having an upper surface and a bottomsurface, wherein the bottom part includes a first electrode and a secondelectrode electrically connecting the upper surface and the bottomsurface of the bottom part, respectively; and a side part having anupper surface including a trench and a bottom surface being in contactwith the upper surface of the bottom part, wherein the upper surface ofthe bottom part is lower than the upper surface of the side part suchthat the package body includes a cavity surrounded by the side part; alight emitting diode disposed on the first electrode; a transparentresin material disposed inside of the cavity; and a wire connecting thelight emitting diode to at least one of the first electrode and thesecond electrode, wherein the upper surface of the bottom part includesa first opened portion that divides the first electrode and the secondelectrode, and the bottom surface of the bottom part includes a secondopened portion that divides the first electrode and the secondelectrode, and wherein a portion of the transparent resin material isdisposed inside of the trench.
 2. The light emitting device according toclaim 1, wherein the light emitting diode is disposed in the cavity. 3.The light emitting device according to claim 1, wherein a lateralsurface of the cavity is inclined.
 4. The light emitting deviceaccording to claim 1, wherein the transparent resin material includes aphosphor material.
 5. The light emitting device according to claim 1,wherein the transparent resin material has an uneven top surface.
 6. Thelight emitting device according to claim 1, wherein the light emittingdiode comprises a plurality of LED chips.
 7. The light emitting deviceaccording to claim 6, wherein the plurality of LED chips emits differentcolor light.
 8. The light emitting device according to claim 1, whereinthe transparent resin material covers the light emitting diode.
 9. Thelight emitting device according to claim 1, wherein the trench has acircular or oval shape.
 10. The light emitting device according to claim1, wherein the trench has a shape different from an outer shape of thecavity.